Portable lower-body stretching apparatus

ABSTRACT

A portable, adjustable apparatus for stretching the muscles of the lower body, in particular, the hip flexor and thigh muscles, comprised of a back support, a flexible line, a knee cradle attached to the mid-portion of the flexible line, and a line tensioning device which receives the free end of the line. The line-tensioning device allows a user to perform flexed-knee stretches such as the knee-to-chest stretch without having to manually hold the knee in the stretched position. The position of the back support and line-tensioning device relative to the knee cradle allows the knee to be drawn directly back towards the chest to optimally stretch the hip flexor and thigh muscles.

This application claims the benefit of provisional patent application No. 61/201,521, filed 2008 Dec. 11 by the present inventor.

FIELD OF THE INVENTION

The present invention is directed to a device used in exercising, and more particularly, to an apparatus for stretching the muscles of the lower body.

BACKGROUND OF THE INVENTION

Flexibility of the hip and thigh muscles is important for athletes. Flexibility of two muscle groups of the lower body—the illiopsoas (hip flexor) muscles in the front of the thigh and the hamstring muscles in the back of the thigh—is particularly important. Although the hamstring muscles are most effectively stretched when the leg is kept in a straightened or extended position, the hip flexors are most effectively stretched when the leg is flexed (i.e., bent at the knee). Given this fact, an exercise that is most effective at stretching the hip flexors is the knee-to-chest stretch, performed one leg at a time while lying supine (face up) on a flat surface. The basic method of performing the knee-to-chest stretch in a supine position is to clasp the knee of one leg with the hands and draw the thigh towards the chest manually by pulling on the knee with the hands. Holding the thigh as close to the chest as possible optimally stretches the hip flexors. After the thigh is held towards the chest for the desired length of time, it is released and the process is repeated with the other leg. The primary disadvantage of performing the knee-to-chest stretch manually is that the subject's arms and hands quickly become fatigued from having to hold the knee in place. Another disadvantage of performing the knee-to-chest stretch manually is that the knee tends to slip out of the subject's hands. A third disadvantage of performing the knee-to-chest stretch manually is that the level of the stretch can't be precisely regulated. A device that would eliminate the need to manually clasp the knee with the hands while performing the knee-to-chest stretch and that would furthermore provide a means of precisely adjusting the level of the stretch, would offer great benefits to persons seeking to enhance the mobility of their hip flexors.

Further Information

Efforts have been disclosed for lower-body stretching devices that assist an athlete in improving their mobility in the hamstring and hip flexor muscle groups. Prior efforts have generally focused more on devices that assist in stretching the hamstrings rather than the hip flexors.

U.S. Pat. No. 5,595,559 to Viel, U.S. Pat. No. 5,634,873 to Carlstrom, and U.S. Pat. No. 6,338,700 to Pollock are examples of supine-position stretching devices in which the user lies on a flat surface, attaches a leg to one end of a rope, then pulls the rope through a pulley located above the user's head. Because each of these devices was designed to stretch the leg in the straightened position, they would have limited utility in stretching the hip flexors. Even if the foot stirrup in these devices were modified to hold the knee, thereby conceivably allowing the device to be used to perform the knee-to-chest stretch, the distance between the pulley and the knee would make the knee unstable, and the position of the pulley relative to the knee wouldn't provide the proper angle for drawing the knee towards the chest. A further drawback to these devices is that they each require an external anchoring point for the pulley, thereby limiting their portability.

U.S. Pat. No. 6,203,473 to Atwood and U.S. Pat. No. 7,309,305 to Nichols are additional examples of supine-position leg stretching devices. Although these devices offer a greater degree of portability than the prior-mentioned efforts, as these devices were similarly designed to stretch the leg in the extended position, they could not properly perform the knee-to-chest stretch and therefore would have limited utility in stretching the hip flexors. A further drawback to these devices is that manual effort is required to hold the stretch in place.

U.S. Pat. No. 4,588,186 to Calabrese and U.S. Pat. No. 5,588,941 to Scott are examples of strap-type lower body exercise devices that include a harness worn around an athlete's upper torso and a loop that would cradle an athlete's foot in various positions. While these devices could conceivably be used to perform the knee-to-chest stretch, there are certain features that seriously limit their utility in performing such stretch. For example, U.S. Pat. No. 4,588,186 to Calabrese provides no means of assisting the user in holding the stretched leg in place. The user must manually grasp cords attached to a loop around the leg to hold the leg while it is being stretched. In addition, both U.S. Pat. No. 4,588,186 to Calabrese and U.S. Pat. No. 5,588,941 to Scott have complex harnesses that must be worn around the upper body and that would be difficult to wear and take off. Furthermore, the strap loops that both of these devices' offer for holding of the leg for stretching or exercising are very narrow in width, and thus would be unlikely to securely and comfortably hold a user's knee in the desired position when performing the knee-to-chest stretch. Lastly, U.S. Pat. No. 5,588,941 to Scott lacks a means of precisely regulating the level of a stretch. The simple strap-tightener located on one side of the device would not allow a user to easily, quickly and precisely adjust the stretch to the desired level.

U.S. Pat. No. 5,624,359 to Dean, U.S. Pat. No. 5,984,845 to Powers, and U.S. Pat. No. 6,368,255 to Chan-Rouse are examples of relatively simple stretching and exercising bands, in loop-like configurations or otherwise. Although these devices could be used to assist an athlete in performing the knee-to-chest stretch, since each of the aforementioned devices requires the athlete to physically hold the ends of the bands in place for the duration of the stretch, no significant benefit of using such devices could be gained over simply performing the stretch manually.

In sum, efforts have been disclosed for a number of lower-body stretching devices, but most efforts have generally focused on devices which require the user's leg to be kept straight. Such efforts would not be helpful in assisting a user in performing flexed-knee stretches, such as the supine-position knee-to-chest stretch. Other efforts for lower-body stretching devices do allow a user to perform stretches while the leg is flexed. However, these efforts suffer from certain defects that make them less-than optimal in performing flexed-knee stretches. Some of the efforts require the user to assume complex harnesses to hold the stretched limb in place, and other devices provide only a narrow strap configured in a loop to hold the knee in place, which would inadequately cradle the knee. Finally, other efforts provide only lengths of strap or bands, one portion of which would grip the stretched limb and another portion of which would be gripped by the user. Since the user must manually hold the stretch with the arms, such efforts would offer no substantial benefits over simply performing flexed-knee stretches such as the knee-to-chest stretch with one's hands.

SUMMARY OF INVENTION

The present invention is directed to a portable, adjustable apparatus intended for the purpose of assisting a user in performing flexed-leg stretches of the lower limbs. The present invention is comprised of an elongated, curved back support the shape of which is intended to substantially conform to the upper back region of a user's back; a knee cradle in which the user's knee rests; a flexible line such as a rope or strap the mid-portion of which carries the knee cradle and which substantially connects the knee cradle to the back support unit; and a releasable line-tensioning device which is attached to the back support unit and which receives the free end of the flexible line. The present invention is designed to allow a user to perform flexed-knee stretches, such as the supine-position knee-to-chest stretch, without the user having to clasp the knee with the hands for the duration of the stretch. The line-tensioning device allows the user to precisely adjust the stretch to the desired level, and a releasable lever located on the line-tensioning device allows the user to release the stretch easily and quickly. The position of the back support and line-tensioning device relative to the knee cradle provide the correct angle necessary to draw the user's thigh directly towards the chest. In a preferred embodiment of the present invention, the knee cradle is slidably attached to the flexible line, thereby allowing the user to freely position the knee along the length of the flexible line such that it will keep in direct alignment with the user's chest. In a preferred embodiment of the present invention, the knee cradle is substantially arcuate in shape to conform to the shape of the user's knee, and contains an interior cushion portion to hold the knee securely and comfortably. The present invention offers the advantages of being lightweight, portable, and easy to put on and take off. Additionally, the present invention is versatile as it can be utilized to perform both relaxed and isometric stretching of the hip flexor and thigh muscles.

BRIEF DESCRIPTION OF THE FIGURES

The subject matter which is regarded as the invention is particularly pointed out and distinctly claimed in the concluding portion of the specification. The invention, however, may be best understood by reference to the following description taken in conjunction with the accompanying drawing figures in which:

FIG. 1 is a perspective drawing of an illustrative portable lower-body stretching apparatus that can comprise the present invention.

FIG. 2 is a plan view of an illustrative portable lower-body stretching apparatus that can comprise the present invention.

FIG. 3 is a perspective view of a user operating an illustrative portable lower-body stretching apparatus that can comprise the present invention.

DETAILED DESCRIPTION AND PREFERRED EMBODIMENT

In FIGS. 1-3, there is shown a portable, lower-body stretching apparatus (10), comprised of a back support (12), a knee cradle (14), a flexible line (16), and a line-tensioning device (18).

The back support (12) is an elongated member, sturdy but pliable in construction, comprised of nylon, leather or other elastomeric material that will conform to the shape of the user's upper back and be comfortable to the user while lying in the supine position. When worn, the back support (12) circumscribes a portion of the user's upper back area, roughly transversing the latissimus dorsi muscles of the upper back, with the ends of the back support (12) located underneath each of the user's arms and resting against the user's ribcage on each side of the user's body. Assuming a user of an average body size and weight, it would be a preferred embodiment of the present invention that the back support (12) would have dimensions of approximately 24-28″ in length, 4-5″ in height, and a maximum of ¼″ in width. It can be understood that larger-than-average users might require a back support (12) of slightly larger dimensions, and smaller-than-average users might require a back support (12) of slightly smaller dimensions.

The knee cradle (14) is attached to the mid-portion of the flexible line (16). The function of the knee cradle (14) is to secure the user's knee and thus keep the thigh from slipping out of place when performing flexed-knee stretches such as the knee-to-chest stretch. In a preferred embodiment, the knee cradle (14) would be substantially concave or arcuate in shape so as to optimally conform to the shape of an average user's knee. In a preferred embodiment, the knee cradle (14) would be comprised of an exterior face portion (26), comprised of a sturdy, lightweight material such as polycarbonate plastic; and an interior cushion portion (28), which would be comprised of a piece of compressed foam rubber or similar durable material that is comfortable to the user's knee and which would be fixably attached to the external face portion (26), by stitched thread, glue or similar fastening means. In a preferred embodiment of the present invention, the knee cradle (14) would have dimensions of approximately 8″ in height, 4-5″ in width, and ¾″ to 1″ in total width (including both the face portion (26) and cushion portion (28) of the knee cradle (14)). Larger-than-average users might require a knee cradle (14) of slightly larger dimensions, whereas smaller-than-average users might require a knee cradle (14) of slightly smaller dimensions.

In a preferred embodiment of the knee cradle (14), two metal loops (30) would be fixably attached to the face portion (26) of the knee cradle (14), forming a channel through which the flexible line (16) would travel. In this preferred embodiment, the knee cradle (14) could be freely positioned at any point along the length of flexible line (16) desired by the user, thereby allowing the user to keep the knee properly aligned with the chest no matter what the length of the flexible line (16) happens to be.

The flexible line (16) attaches the knee cradle (14) to the back support (12). The first end of the flexible line (16) is fixably attached to one end of the back support (12) by means of a rivet or similar fastening means. The second end of the flexible line travels through the line-tensioning device (18). The middle portion of the flexible line (16) carries the knee cradle (14). In a preferred embodiment, the free end of the flexible would include a handle, loop or similar gripping means (20), which would allow the user to easily draw the flexible line (16) through the line-tensioning device (18). If a handle (20) were used as a gripping means, such handle (20) could be made of plastic or similar material and could be attached by means of a rivet or similar fastening means. In a preferred embodiment, the flexible line (16) will have a total length of approximately 48-50″, and a diameter of approximately ¼″. A flexible line (16) length of 48-50″ should generally be sufficient to accommodate users of different sizes and to provide a maximum range of motion to users having varying levels of mobility in their hip flexors. The flexible line (16) could be comprised of a rope, plastic or steel cable, steel cable sheathed in plastic, or flat strap, as long as the material used was sufficiently strong and had a surface that could be effectively gripped by the line-tensioning device (18).

An essential part of the present invention is the line-tensioning device (18). The objective of the line-tensioning device (18) is to allow the flexible line (16) to travel freely through it in one direction, but not the other. By carrying out this objective, the line-tensioning device (18), in conjunction with the back support (12) and knee cradle (14), allows the user to draw a lower-limb into a stretched position and then hold that position without manual effort. The line-tensioning device (18) contains an appendage (22) which would be fixably attached to the back support (12) by means of a rivet or similar fastening means, and a release lever (20) which would release the line-tensioning mechanism included therein. There are numerous devices currently on the market for line-tensioning or cinching devices; these can take the form of ratchet pulleys, clutch pulleys, rope-cinching devices, and strap buckles. For example, the line-tensioning device (18) could be comprised of a ratchet pulley similar to that shown in U.S. Pat. No. 5,368,281 to Skyba, a rope-cinching device similar to that shown in U.S. Pat. No. 4,912,817 to Sandreid, or a strap buckle such as that shown in U.S. Pat. No. 3,678,542 to Prete, Jr.

In a preferred embodiment of the present invention, the line-tensioning device (18) would be comprised of a releasable ratchet pulley similar to that shown in U.S. Pat. No. 5,368,281 to Skyba. The device shown in U.S. Pat. No. 5,368,281 to Skyba is essentially comprised of a rotatable sheave (not shown in the accompanying figures) and a release lever (20), housed in a sturdy, compact plastic casing. The device is designed such that rotation of the sheave is permitted in one direction but not the other, unless the release lever (20) is depressed. The advantages of using a ratchet pulley similar to U.S. Pat. No. 5,368,281 to Skyba is that such a device is capable of securely gripping a rope even when under extreme tension. Having said this, it can be appreciated that any number of devices apart from a ratchet pulley similar to U.S. Pat. No. 5,368,281 to Skyba could be effectively used as a line-tensioning mechanism (18), without exceeding the scope of the present invention.

PREFERRED MODE OF OPERATION

FIG. 3 is an illustration of a user performing the knee-to-chest stretch with the assistance of an example of the present invention. FIG. 3 shows how the present invention allows a user to maintain the knee-to-chest stretch without the use of his arms. Further details on the preferred mode of operating the present invention are provided below. The user first dons the apparatus (10) by raising the back support (12) over the head, and then lowering the back support (12) through the arms until it is located around the upper back with its ends located underneath each of the user's arms and resting against the user's ribcage on each side of the body. The user then lies on his back on a flat surface, such as a mat, preferably with a cushion to support his head. After making any final adjustments to the position of the back support (12), the user then places one of his knees in the knee cradle (14). Once the user's knee is comfortably secure in the knee cradle (14), he draws the flexible line (16) through the line-tensioning device (18) by pulling on the handle (24) with one of his arms. Drawing the flexible line (16) through the line-tensioning device (18) causes the length of flexible line (16) between the far end of the back support (12) and the line-tensioning device (18) to shorten, thereby causing the knee cradle (14) to be drawn towards the user's chest. The more the user pulls on the handle (24), the close the user's knee (which rests in the knee cradle (14) comes to the chest, and the greater the hip flexor muscles are stretched. Once the desired level of stretch in the hip flexors are achieved, the user may release the handle (24), as the line-tensioning device (18) will prevent the flexible line (16) from traveling in the reverse direction. After the stretch is held for a sufficient time, the user depresses the release lever (20) on the line-tensioning device (18), which releases its grip on the flexible line (18), thereby allowing the user's thigh to fall away from his chest. After having completed the stretch on one leg, the user may then perform the stretch with the other leg if desired.

Isometric Knee-to-Chest Stretch

In addition to performing relaxed stretching of the hip flexor muscles with the present invention, the present invention can also be used to perform isometric stretching of the hip flexor muscles. Isometric stretching has been shown to provide more rapid gains in static passive flexibility of a muscle than performing relaxed stretching of the muscle alone. In isometric stretching, the athlete uses positions similar to those used in relaxed stretching, but briefly tenses or contracts the muscle immediately prior to the stretch. When an isometric knee-to-chest stretch is performed manually, the tensing of the hip flexor muscle would be accomplished by pushing the knee against the restraining force of the hands clasping the knee. However, when an isometric knee-to-chest stretch is performed with the assistance of the present invention, the tensing of the hip flexor muscle would be accomplished by pushing the knee against the knee cradle (14). Because the knee cradle (14) holds the knee in place more securely and with less effort than the hands, the isometric knee-to-chest stretch would more effectively be performed using the present invention than if such stretch were performed manually. 

1. A portable, adjustable lower-body stretching apparatus comprising: (a) a back support member which circumscribes a portion of an upper back; (b) a knee cradle member; (c) a releasable line-tensioning member which is fixably attached to an end of said back support member; and (d) a flexible line member, one end of which is fixably attached to an end of said back support member, a proximate middle portion of which locates said knee cradle member, and a free end of which communicates with said line-tensioning member, wherein the improvement comprises providing a mechanically-assisted means of performing flexed-knee stretches without having to manually hold said knee with the hands.
 2. The lower-body stretching apparatus of claim 1 wherein said back support member is substantially elongated in shape and comprised of an elastomeric material that will conform to the shape of the user's back and be comfortable to the user while lying in the supine position.
 3. The lower-body stretching apparatus of claim 1 wherein said knee cradle member is slidably attached to said flexible line member.
 4. The lower-body stretching apparatus of claim 1 wherein said knee cradle member is substantially arcuate in shape and is comprised of an exterior face portion and an interior cushion portion, said interior cushion portion being substantially comprised of a padding material to comfortably and securely hold the user's knee in place.
 5. The lower-body stretching apparatus of claim 1 wherein the free end of said flexible line member further includes a loop, handle, or similar gripping means.
 6. The lower-body stretching apparatus of claim 1 wherein said line tensioning member consists of a ratchet pulley, said ratchet pulley containing a rotatable sheave and a releasable ratchet which permits the sheave to rotate in one direction but not the other, unless the release is activated.
 7. The lower-body stretching apparatus of claim 6 wherein said back support member is elongated in shape and comprised of an elastomeric material that will conform to the shape of the user's back and be comfortable to a user while lying in a supine position.
 8. The lower-body stretching apparatus of claim 6 wherein said knee cradle member is slidably attached to said flexible line member.
 9. The lower-body stretching apparatus of claim 6 wherein said knee cradle member is substantially arcuate in shape and is comprised of an exterior face portion and an interior cushion portion, said interior cushion portion being substantially comprised of a padding material to comfortably and securely hold the user's knee in place.
 10. The lower-body stretching apparatus of claim 6 wherein the free end of said flexible line member further includes a loop, handle, or similar gripping means.
 11. The lower-body stretching apparatus of claim 1 wherein said flexible line consists of a substantially flat strap, and said line-tensioning member consists of an adjustable strap buckle, said buckle having means of securably holding and releasing said strap.
 12. The lower-body stretching apparatus of claim 11 wherein said back support member is elongated in shape and comprised of an elastomeric material that will conform to the shape of the user's back and be comfortable to a user while lying in a supine position.
 13. The lower-body stretching apparatus of claim 11 wherein said knee cradle member is slidably attached to said flexible line member.
 14. The lower-body stretching apparatus of claim 11 wherein said knee cradle member is substantially arcuate in shape and is comprised of an exterior face portion and an interior cushion portion, said interior cushion portion being substantially comprised of a padding material to comfortably and securely hold the user's knee in place.
 15. The lower-body stretching apparatus of claim 11 wherein the free end of said flexible line member further includes a loop, handle, or similar gripping means.
 16. A method of stretching the hip flexor and thigh muscles in a supine position, comprising: (a) providing a lower-body stretching apparatus comprising: (i) a back support member which circumscribes a portion of an upper-back; (ii) a knee cradle member; (iii) a releasable line-tensioning member, fixably attached to an end of said back support member; and (iv) a flexible line member, one end of which is fixably attached to an end of said back support member, a proximate middle portion of which locates said knee cradle member, and a free end of which communicates with said line-tensioning member. (b) lying on a surface in a generally upward direction; (c) engaging the upper back region with said back support member; (d) engaging the frontal portion of one leg with said knee cradle member; and (e) drawing the thigh of the leg towards the chest by pulling said flexible line member through said line-tensioning member, wherein the improvement comprises providing a method of performing flexed-knee stretches without having to manually hold said knee with the hands.
 17. The method of claim 16 wherein said line tensioning member consists of a ratchet pulley, said ratchet pulley containing a rotatable sheave and a releasable ratchet which permits the sheave to rotate in one direction but not the other, unless the release is activated.
 18. The method of claim 16 where said flexible line member consists of a substantially flat strap, and said line-tensioning member consists of an adjustable strap buckle, said buckle having means of securably holding and releasing said strap. 